# arr = [123213, 123123, 213123]
# """[list]
# 增 删 改 查
#     """

# arr.append(5)
# arr.append(5)
# print(arr.remove(5))
# print(arr, '==result=='*5)

# cars = ['bmw', 'audi', 'toyota', 'subaru']
# cars.sort(reverse=True)
# a = sorted(cars, reverse=False)
# cars.reverse()
# l = len({'a': 1, 'b': 2})
# for c in cars:
# print(c)
# for i in range(0, 11, 2):
# print(i)
# obj = {i for i in range(5)}
# print({i for i in range(5)})
# ccc = cars.copy()
# ccc.append(1)

# t = ({'a': 55}, 3, 4)
# t[0]['a'] = 66
# for i in t:
#     print(i)
# li = [{'a': 123}]
# arr = [val for val in li]
# arr[int(0.0)]
# import random
# arr = [i for i in range(10)]
# b = arr.index(1)
# arr2 = [i for i in range(11, 20)]
# print(random.randint(0, 2))
# print(arr * 2)
# import copy
# arr = [{'a': 66}]
# a = copy.deepcopy(arr)
# arr[0]['a'] = 77
# print(a)

def fn(cb):
    cb and cb('hello fn')


fn(lambda x: print(x))

obj = {'a': 12356}

print(obj.get('b'))
